無限 むげん かい微分 びぶん可能 かのうではありません
mugenka ibibunkano udewa arimasen

Desu Copula
na-Adjective
Negation Auxiliary

The polite negative form of 無限回微分可能

1. Not infinitely differentiable.; Not possible to infinitely differentiate.

Negative
Polite
Formal Register
Mathematics